In this proposal we request partial support for the 16th , 17th and 18th Biennial Gordon Research Conferences on Mammary Gland Biology. The sixteenth conference will be held June 3-8, 2001 at Roger Williams University, Bristol, Rhode Island. The site and dates for the 17th and 18th conferences have not been set, but are expected to be in similar time period in 2003 and 2005, at one of the approved GRC sites. Roger Williams College is a new venue for this conference. It features excellent accommodations and a pleasant location that should prove productive for personal interactions. The Mammary Gland Biology conference has traditionally been highly successful, bringing together scientists from various disciplines who share a common interest in the Mammary gland. The 2001 program has been designed with the aim of satisfying this multidisciplinary audience. The Program includes: An overview in which recent progress in three broad areas, Endocrinology, Development, and Cancer, are summarized, new directions are pointed out, and unsolved problems or ambiguities are brought to attention. Not only will this provide an exciting introduction, but importantly, will also encourage audience participation at early stage in the conference. Subsequent sessions focus on Tissue interactions; IGF in development and cancer; Cell identity, Differentiation and function; Tumor progression and Metastasis; Genome stability/DNA repair; The lactation cycle; and Signal Transduction. One plenary speaker slot in each sessions will remain open for a time, permitting later selection of "hot" topics. The 2003 conference program is not yet set, but will continue the highly successful interdisciplinary tradition. Conference presentations and discussions will not be published, recorded, or cited. This policy encourages conferees to engage in informal discussions and multidisciplinary interactions. The large increase in mammary biomedical research brought about increased funding through the NIH and the U.S. Army sponsored program, has important implications to health scientists in any disciplines, so this interdisciplinary approach, so successful in the past, now has even greater potential. Conference funding is requested in support of those who invited speakers whose topics were related to those of the NIH, as well as to support the increasing participation of junior scientists, as well more experienced researchers, becoming interested in mammary gland biology and in the breast cancer problem.